The present invention relates to a positional deviation correcting method for a subject to be inspected, in which the positional deviations of the subject such as positional deviations of variable resistors and so on mounted on a printed circuit board are automatically detected and corrected.
Heretofore, there is known a positional deviation correcting method for a subject conveyed on a production line shown in FIG. 1. As shown in FIG. 1, a pallet 52 mounted thereon with a subject, namely a printed circuit board in this case, is conveyed on a conveyor 51. Along the conveyor line are arranged stations 53, 54, 55 and 56, and each of these stations is provided with a recognizing means for recognizing the positions of such as variable resistors, variable capacity coils, trimmer condensers and so on, and with a movable adjusting means for adjusting the positions of the above-mentioned variable resistors and so on. A standard pallet mounted with variable resistors and so on at standard positions is conveyed by a conveyor 51, and these standard positions are recognized and stored at these stations 53, 54, 55 and 56. Then, a printed circuit board, namely a subject to be inspected, is conveyed by the conveyor 51, and the actual positions of variable resistors mounted on the printed circuit board are recognized at the stations 53, 54, 55 and 56, where the recognized actual positions of the resistors are compared with the recognized standard positions of the same, and the positions of the resistors are corrected on the basis of the deviations of the actual positions from the standard positions by use of an adjusting means.
In the above prior art, however, it is required to provide a recognizing means at every station 53, 54, 55 and 56, thereby causing a problem that the cost for practicing this method becomes high and the tact time on the production line becomes long.